The other way to deal with provision of public good is to ask the agents about their preferences and, basing on the answers, decide about the proportion of outlay that agents have to bear. But the simple rule of imposing the tax proportionally to the reported preference may lead to dishonest answers. %This problem was referred in the "Free rider" section \ref{sec:fr}. 

It is important to say that even though lack of mechanism do not guarantee that any agent contributes a penny, experiments show that the opposite assumption neither is true.\cite{bk:ledyard93}

Thereby, in order to make our solution more predictable, let's introduce a mechanism which could prevent society from the free rider problem and give results closer to pareto-optimal frontier.

At first we will try to apply some already invented mechanisms and find their Nash equilibria. Then we shall evaluate the supposed results by the means of inequality metrics.

